Cam-clamp.



A; P. BULL.

} CAM CLAMP.

APPLICATION FILED MAY 23. 1918.

Patented Mar. 18, 1919 Mme/15o ADRIAN P. BULL, 0F RAVENNA, OHIO.

CAM-CLAMP.

To all whom it may concern:

Be it known that I, ADRIAN P. BULL, a citizen of the United States,residing at Ravenna, in the county of Portage and State of Ohio, haveinvented certain new and useful Improvements in Cam-Clamps; and I dodeclare the following to be a full, clear, and exact description of theinvention, such as will enable others skilled in the art to which itappertains to make and use the same.

My invention relates to improvements in clamps and more particularly tothose used principally by pattern makers, it being my object to providea comparatively simple and inexpensive clamp of this class which willhold work of difl'erent thicknesses to equal advantage without thenecessity of using chips and the like between the stock and one of thejaws as is now commonly done.

With the foregoing general object in view, the invention resides in thenovel construction of the clamp hereinafter fully described and claimed,the descriptive matter being supplemented by the accompanying drawingwhich forms a part of this application and in which:

Figure 1 is a side elevation of the clamp;

Fig. 2 is a top plan View;

Fig. 8 is a vertical longitudinal section on the plane of the line 3-3of Fig. 2;

Fig. 4 is a vertical transverse section on the plane designated by theline 4-4 of Fig. 2; and

Fig. 5 is a perspective view of the removable plate upon which the camoperates to depress the jaw.

In the drawing above briefly described, the

numeral 1 designates a base from which a preferably fiat standard 2extends, any suitable means 3 being employed for securing the standardto the base. A rectangular jaw 4 is provided with a central openlng 5receiving the standard 2 in such a manner as to permit said jaw to slidetoward and away from the base, and directly above the jaw 4 the outerend of the standard 2 is provided with a longitudinal slot 6 into whoseouter end a set screw 7 projects, said set screw being threaded in thestandard as shown clearly in Figs. 3 and 4. The furcations 8 of abifurcated cam straddle the standard 2 above the wall 4 and are providedwith a fulcrum pin 9 located eccentrically and extending through theslot 6, the position of said fulcrum pin in the slot being controlled bythe set screw 7, so that the cam and jaw Specification of LettersPatent.

Patented Mar. 18, 1919.

Application filed May 23, 1918. Serial No. 236,156.

may be adjusted toward and away from the base 1 according to thethickness of the work to be clamped. Any suitable handle 10 may beprovided for operating the cam, but said handle is by preference in theform of a I l straddling the standard 2 as seen clearly in Figs. 3 and4. The upper side of plate 12 is provided with lugs 13 upon which thefurcations 8 of the cam operate to force the jaw 4 toward the base 1,against the tension of a pair of coiled springs 14 which raise said jawas soon as the cams are released. These springs preferably surround pins15 rising rigidly from the base 1 with their upper ends receivedslidably in openings 16 in the jaw, and since the springs in questionexert a constant upward thrust on said jaw, the lugs 13 are held incontact with the furcations 8 of the cam so that the plate 12 is heldagainst accidental removal from the socket 11. Whenever required, thisplate may be removed and one having larger lugs 13 may then besubstituted, so that the jaw 4 may be depressed to a greater extent thanthat allowed by adjusting the set screw 7 downwardly to the maximum.Also, by inserting a plate such as 12 with relatively thin lugs 13 theclamp may be opened a greater distance than would otherwise be ossible.

In use, the work is clamped etween the jaw 4 and the base 1 by firstsuitably adjusting the cam by means of the set screw 7, and thendepressing the lever 10. The clamp may remain in this condition untilthe work is shaped as required, whereupon raising of the handle willallow the springs 14 to release the clamp. Whenever it is required,another plate having either thicker or thinner lugs 13 is substitutedfor the plate 12 previously used, according to the thickness of the workto be clamped.

From the foregoing, taken in connection with the accompanying drawing,it will be obvious that although In invention is of comparatively simplean inexpensive nature, it will be highly efficient and in every waydesirable. Since probably the best results are obtained from the detailsshown and described, they are by preference followed, but within thescope of the invention as claimed, considerable latitude is allowed.

' for making such minor changes as occasion may dictate. Furthermore, itis to be understood that the use of the device is not limited to anyparticular field.

I claim:

1. A work clamp comprising a base, a standard extending from said baseand having a longitudinal slot, a jaw slidable on said standard, a camfor forcing said jaw toward said base, said cam having a fulcrumpositioned slidably in said slot, and a set screw threaded in the'outerend of said standard and projecting into said slot with itsinner endbearing against said fulcrum, whereby to adjust the latter in said slotaccordingto the thickness of the work.

2. A work 'clam-pcomprising a base, a

standard extending from said base, a jaw slidable on said standard andhaving in its back a socket through which said standard passes, abifurcated plate received removably in said socket with its furcationsstraddling said standard, and a bifurcated cam whose furcations straddlesaid standard and are fulcrumed. thereto, said furcations operating uponthe f'urcations of said plate to force said jaw toward said base.

In testimony whereof I havehereuntoset my hand. v v V ADRIAN P. BULL.

Witnesses MARTHA DUssE'L,

J. H. DUSSEL.

, Copies of this patent may be obtained for five cents each, byaddressing the Commissioner of Iatents,

. v Washington, D. G.

